OBJECTIVES: The prevalence of Autism Spectrum Disorders (ASDs) has been increasing lately and treatment is expensive. Private insurers have historically provided lesser coverage for autism-related services than public insurers. This study compared the differences in health care expenditures and utilization between publicly and privately insured children with ASDs.  METHODS: Data were from years 1997-2010 of the Medical Expenditure Panel Survey. 477 children with ASDs, of which 274 were privately insured and 184 had public insurance only, were identified. Expenditure measures (in 2010 dollars) included total health, home health and prescription expenditures and out-of-pocket expenditures on health and drugs. Utilization measures included the number of office-based visits, home health days and prescriptions. Generalized linear models, adjusted for sociodemographics and health status, were used to model utilization and expenditure to account for their skewness. STATA survey commands generated nationally representative estimates. RESULTS: Average total health care expenses were comparable for publicly and privately insured children with the latter having much higher out-of-pocket expenses ($1137.807 vs $199.244). Publicly insured children used more prescriptions (13.52 vs 9.19) with lower out-of pocket expenses ($103.170 vs $206.964), and used more home health services (19.39 vs 7.67) with higher costs ($3,118.28 vs $782.43). After adjusting for sociodemographic differences and health status, no statistically significant differences in total health expenditures and utilization measures remained. However, publicly insured children spent 79% less (p <0.000) and 63% less (p = 0.001) on average than privately insured children on out-of-pocket health and prescription expenditures respectively. CONCLUSIONS: Higher out-of-pocket expenditures on health services and prescriptions for privately-insured children may be an indication of lower coverage for autism-related health services. State policies should correct this anomaly to reduce the burden on public insurers, as well as provide children with ASDs more options to get expensive treatment options covered.